The present disclosure relates to modules for heat exchange for use in cooling towers and methods of assembling cooling towers using such modules. The aforementioned modules for heat exchange may include fill packing and a structural system configured to provide support for at least the fill packing, in which the structural system includes a plurality of structural members configured to provide compression and tension support. The aforementioned modules for heat exchange may be assembled prior to being transported to a job site and installed in a cooling tower. A method for assembling a cooling tower using the aforementioned modules for heat exchange includes: constructing a cold water basin; assembling an air inlet structure on the cold water basin; and placing a heat exchange module on top of the air inlet structure.
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1. A method for assembling a cooling tower, the method comprising:
assembling a heat exchange module, the heat exchange module comprising fill packing and a structural system configured to provide compression and tension support for the cooling tower;
placing the heat exchange module when assembled on a carrier; and
transporting the heat exchange module on the carrier to a site of the cooling tower,
wherein the structural system is configured to provide compression and tension support for the fill packing during transportation of the heat exchange module,
wherein the structural system comprises a triangular support structure, the triangular support structure configured to transfer a load from a base of the heat exchange module to a center portion of the heat exchange module.
14. A method for assembling a cooling tower, the method comprising:
constructing a cold water basin;
assembling an air inlet structure on the cold water basin; and
placing a heat exchange module on top of the air inlet structure,
wherein the heat exchange module comprises fill packing and a structural system,
wherein the heat exchange module is assembled prior to being placed on top of the air inlet structure,
wherein the structural system is configured to provide compression and tension support for the fill packing when the heat exchange module is assembled and prior to the heat exchange module being placed on top of the air inlet structure,
wherein the structural system comprises a triangular support structure, the triangular support structure configured to transfer a load from a base of the heat exchange module to a center portion of the heat exchange module.
2. The method of
wherein the overhang portion corresponds to a portion of the heat exchange module overhanging a surface of the carrier on which the heat exchange module is placed for transportation.
3. The method of
inserting a fork of a forklift machine below a base of the heat exchange module;
lifting the heat exchange module using the forklift machine;
placing the heat exchange module on the carrier from a side of the carrier,
wherein the base of the heat exchange module comprises a plurality of transverse structural members disposed below a plurality of longitudinal structural members;
wherein the fork is inserted below the base of the module parallel to the transverse structural members and in contact with the longitudinal structural members.
4. The method of
5. The method of
6. The method of
7. The method of
constructing a cold water basin at the site of the cooling tower;
assembling an air inlet structure on the cold water basin;
placing the heat exchange module on the air inlet structure; and
coupling the heat exchange module to the air inlet structure.
8. The method of
9. The method of
wherein the support system of the cooling tower is configured to provide support to the cooling tower when the cooling tower is assembled.
10. The method of
assembling a plenum module, the plenum module comprising a different structural system; and
placing the plenum module on top of the heat exchange module.
11. The method of
12. The method of
wherein the pipe system comprises a header pipe and a branching pipe,
wherein the heat exchange module is configured to provide support for the pipe system.
13. The method of
15. The method of
wherein the support system of the cooling tower is configured to provide support to the cooling tower when the cooling tower is assembled.
16. The method of
wherein the plenum module comprises a different structural system,
wherein the plenum module is assembled prior to being placed on top of the heat exchange module,
wherein the different structural system of the plenum module is configured to form a different portion of the support system of the cooling tower.
17. The method of
wherein the pipe system comprises a header pipe and a branching pipe,
wherein the heat exchange module is configured to provide support for the pipe system.
18. The method of
19. The method of
wherein the heat exchange module is coupled to the air inlet structure at a point along a length of a horizontal structural member.
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The present disclosure relates generally to modules for heat exchange for use in cooling towers. The present disclosure also relates to methods of assembling cooling towers using modules for heat exchange. More particularly, the present disclosure relates, for example, to fill layer modules that can be pre-assembled in a factory setting and transported to a job site and installed in a cooling tower.
Cooling towers are heat exchangers of a type widely used to emanate low grade heat into the atmosphere and are typically utilized in electricity generation, air conditioning installations, and the like. These towers receive a relatively warm or hot fluid, and pass the fluid through the tower apparatus so that heat is extracted from the fluid by interaction with relatively cooler ambient air.
Cooling towers generally include counter-flow type cooling towers and cross-flow type cooling towers. In a counter-flow cooling tower, liquid of high temperature is cooled as it flows downwards through fill or packing and is brought into contact with air traveling upwards. Conversely, in a cross-flow cooling tower, liquid of high temperature is cooled with air that moves horizontally through the fill or packing.
A drawback associated with current cooling towers is that they are typically very labor intensive in their assembly at the job site. The assembly of such towers oftentimes requires a dedicated labor force investing a large amount of hours. Accordingly, such assembly is labor intensive requiring a large amount of time and therefore can be costly. Uncertainties such as weather and site conditions may also affect the time required to assemble cooling towers at a job site. The quality of the labor force may also lead to quality and performance issues associated with the towers. Thus, it is desirable to assemble as much of the tower structure at the manufacturing plant or facility, prior to shipping it to the installation site.
But while it may be desirable to assemble tower components at a factory, conventional designs for cooling towers oftentimes necessitate their assembly at a job site. For example, factors such as the size of the various tower components and their structural strength may limit their ability to be manufactured at the factory and transported onsite.
Therefore, it is desirable to have a cooling tower that is assembled using components that can be manufactured in a factory and transported to a job site.
Embodiments of the present disclosure advantageously provides for a module cooling tower and methods for assembling such a cooling tower. These methods can be applied to counter-flow or cross-flow cooling towers.
An embodiment of the disclosure is a heat exchange module for use in a cooling tower comprising: fill packing; and a structural system configured to provide support for at least the fill packing, in which the structural system includes a plurality of structural members configured to provide compression and tension support.
Another embodiment is a heat exchange module for use in a cooling tower comprising: fill packing; and a triangular support structure comprising a plurality of structural members, in which the heat exchange module is configured to be transportable, and the triangular support structure is configured to provide support for the heat exchange module when the heat exchange module is transported.
Another embodiment is a heat exchange module for use in a cooling tower comprising: fill packing; and a firewall structure, in which the heat exchange module is configured to be transportable, and the firewall structure is configured to withstand dynamic loads when the heat exchange module is transported.
Another embodiment is a method for assembling a cooling tower, the method comprising the steps of: assembling a heat exchange module, the heat exchange module comprising fill packing and a structural system; placing the heat exchange module when assembled on a carrier; and transporting the carrier to a site of the cooling tower.
Another embodiment is a method for assembling a cooling tower, the method comprising the steps of: constructing a cold water basin; assembling an air inlet structure on the cold water basin; and placing a heat exchange module on top of the air inlet structure, in which the heat exchange module is assembled prior to being placed on top of the air inlet structure and comprises fill packing and a structural system.
There has thus been outlined, rather broadly, certain embodiments of the invention in order that the detailed description thereof herein may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional embodiments of the invention that will be described below and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of embodiments in addition to those described and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
The above-mentioned and other features and advantages of this disclosure, and the manner of attaining them, will become more apparent and the disclosure itself will be better understood by reference to the following description of various embodiments of the disclosure taken in conjunction with the accompanying figures.
In the following detailed description, reference is made to the accompanying drawings, which form a part hereof and show by way of illustration specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice them, and it is to be understood that other embodiments may be utilized, and that structural, logical, processing, and electrical changes may be made. It should be appreciated that any list of materials or arrangements of elements is for example purposes only and is by no means intended to be exhaustive. The progression of processing steps described is an example; however, the sequence of steps is not limited to that set forth herein and may be changed as is known in the art, with the exception of steps necessarily occurring in a certain order.
Cooling towers regulate the temperature of relatively warm or hot fluid by passing the fluid through a tower apparatus that brings it into contact with relatively cooler ambient air. These towers typically include a hot liquid distribution system. Examples of these distribution systems may have a series of water distribution nozzles or an apertured distribution basin or the like, and a cold water collection basin positioned at the base or bottom of the cooling tower. Commonly, a splash-type water dispersing fill structure is disposed in the space between the hot water distribution system and the underlying cold water collection basin. The aforementioned fill structure oftentimes includes either a plurality of elongated, horizontally arranged and staggered splash bars supported at spaced intervals by an upright grid structure or frame assembly, or a series of fill packs or fill packing composed of a number of film fill sheets. During assembly of the evaporative cooling towers, typically, an outer shell or support structure is built first and then a rack or grid support is affixed to the support shell. Splash bars are then threaded into the rack. The splash bars generally provide a surface for consistent, predictable dispersal and breakup of the water droplets over a range of water loadings typically encountered during operation of the evaporative cooling tower. Typically, these splash bars are long and thin and the fill structure includes a great number of them. Alternatively, during assembly, fill packs may be employed and installed into the support structure of the cooling tower.
In a counter-flow tower, the liquid to be cooled is pumped in and distributed over the fill structure so that air which is drawn in from below serves to cool the liquid being distributed through the fill structure. These towers typically include an air inlet region that is disposed below the fill layer for drawing in the ambient air, and a plenum chamber above the fill layer for receiving the air after it travels through the fill layer. The air is then released into the atmosphere via a fan located at the top of the cooling tower. In a cross-flow tower, the liquid to be cooled is again distributed over the fill structure but is met with air that moves horizontally through the fill structure. Similar to the counter-flow tower, the cross-flow tower has an air inlet region which generally corresponds to the height of the fill structure and a plenum chamber.
Systems and methods disclosed herein provide a cooling tower having an air inlet structure, a fill module including the fill structure, and a plenum module. Various components of the air inlet structure, fill module, and plenum module may be pre-assembled in a factory prior to being installed in the cooling tower. These components may be adapted to be easily handled for transportation and quick assembly at a job site. Thus, systems and methods disclosed herein provide a process for constructing a cooling tower using pre-assembled modular components.
In systems and methods disclosed herein, the fill module may be preassembled in a factory. The fill module may be an example of a heat exchange module. The fill module may include fill packs or splash fill packing and a supporting structure. As described above, the fill packs or splash fill packing comprise film fill packing. The fill packs are notched at the factory so that the structure can be packaged around the fill packs. The fill modules are then aligned with one another using alignment tubes prior to transportation to a job site. The fill modules may be transported by loading them onto flatbed trailers using a special forklift. The fill modules may be secured to the flatbed trailers with tie-down members such as, for example, a U-shaped bolt. When the fill modules arrive at the job site, the modules may be hoisted from the trailer using a specially designed lift fixture and placed directly onto a structure such as an air inlet structure which has been pre-assembled at the job site. The fill module may then be aligned and connected to surrounding structure using specially designed corbels.
Systems and methods disclosed herein also provide a structural system for a fill module for transporting the assembled fill module to a job site. Fill layers in conventional cooling towers typically comprise a fiberglass structure which lacks sufficient bending strength to withstand transportation. Thus, to overcome this problem, systems and methods disclosed herein provide for a structural system with sufficient flexural and tensile strength to withstand dynamic loads during transportation.
Moreover, systems and methods disclosed herein provide a global structural system for a cooling tower having solid structural members at every elevation of the tower or, specifically, in the air inlet structure, the fill module, and plenum module or structure. Conventional cooling towers that are constructed at a job site typically have a supporting structure comprising tension/compression hard diagonals. Fill structure designs, however, that are inserted into such cooling towers do not incorporate permanent primary structure as a part of its design. Moreover, many conventional cooling towers comprise tension-only supporting members such as, for example, small rods or thin straps. The tension-only members provide little to no compressive resistance and therefore buckle under compression loads. While these tension-only members may be smaller than tension/compression members, these tension-only members are not permitted in some structural applications, particularly in seismic applications.
Accordingly, systems and methods disclosed herein provide a global structural system that is designed in three different portions—specifically, a first portion in an air inlet structure, a second portion in a fill module, and a third portion in a plenum module or structure. In particular, such systems and methods provide a structural frame for a fill module that forms a portion of the permanent tower system. Each portion of the structural system is designed to withstand its own heaviest load combination. In other words, each portion of the structural system is designed to take into account the portions above it that transmit loads to the lower portions.
Moreover, systems and methods disclosed herein provide a structural system having a king post design for supporting the fill module during transportation. The structural system may include tension-only diagonals that are disposed symmetrically about a central tension/compression member or “king post.” When the fill module is transported, the bottom of the fill module may sit on a flatbed of a truck having a width less than the width of the fill module. Accordingly, if the fill module is centered on the flatbed, two portions of the fill module may overhang the sides of the flatbed. Such portions may be referred to as the “overhang portions.” The tension-only diagonals of the structural system may carry loads from the overhang portions of the fill module to the top of the king post, and the king post may deliver a compressive force downward towards the middle of the module at the center of the truck. Without the tension-only diagonals, the size of the horizontal members may need to be increased in order to carry the load of the fill module overhanging the flatbed truck during transportation. Increasing the size of these horizontal members may be costly and also add to the weight of transportation. In comparison, the tension-only diagonals are relatively inexpensive. Accordingly, systems and methods disclosed herein provide a less costly solution for transporting a fill module to a job site.
Systems and methods disclosed herein also provide a fill module that is ready or nearly ready for installation into a cooling tower when it arrives as a job site. In specific applications, systems and methods may provide a fill module that can be hoisted from a carrier and installed in a cooling tower within fifteen (15) to thirty (30) minutes.
Systems and methods disclosed herein also provide a fill module comprising a height less than a conventional fill layer of a cooling tower. In particular, a typical fill layer including, for example, a MC75 counter-flow film fill of five (5) feet may be eight (8) feet and four (4) inches. Other examples of fill may include a DF254 counter-flow film fill of five (5) feet and four (4) inches, or a MVC20 counter-flow film fill of four (4) feet and eight (8) inches. Systems and methods disclosed herein may provide a fill module including fill with the same height but having an overall module height of seven (7) feet and two (2) inches.
Systems and methods disclosed herein also provide corbels designed with alignment holes that can be used to connect various structures of the cooling tower to one another. For example, such systems and methods may provide a corbel that is designed to connect a fill module with an air inlet structure. In conventional cooling towers, column splices may occur between the different stories or levels of the tower. Spliced columns may be undesirable because the splice is perceived as not being as structurally sound as a continuous column and raises concerns about the bearing of one column on top of another column if they are misaligned. To avoid these problems, systems and methods disclosed herein connect the various structures of a cooling tower to one another using corbels. Such systems and methods may connect the various structures to one another at a girt line or horizontal structural member, further adding to the strength of the overall structure.
Systems and methods disclosed herein also provide a fill module having bottom girts arranged such that a layer of transverse girts are disposed below a layer of longitudinal girts. Such an arrangement allows for a lifting fork to be easily inserted along the bottom of the fill module from its side. In particular, the lifting fork may be inserted along the base of the fill module with the forks parallel to the transverse girts and in contact with the longitudinal girts. Because the fill module is adapted to allow the fork to be directly inserted below its bottom base, the fill module may be transported without a wood pallet or the like, which reduces the cost and time of transportation. Accordingly, such systems and methods disclosed herein provide a fill module adapted for more efficient transportation to a job site.
Systems and methods disclosed herein also provide a fill module having top girts arranged such that a layer of transverse girts are disposed above a layer of longitudinal girts. Such an arrangement may provide elevation for a water distribution system positioned above the fill module. The added elevation may provide additional vertical space for the nozzles of the water distribution system to distribute the water over the fill packing within the fill modules.
Systems and methods disclosed herein also provide a fill module having a firewall adapted for transportation. The firewall may be pre-installed in the fill module prior to being transported to a job site. Unlike conventional firewall structures formed of fiber-reinforced cement that may be too brittle to withstand dynamic movements during transportation, the firewall disclosed herein may be formed of a fire-resistant fiber-reinforced polymer that has sufficient flexural and tensile strength to withstand transportation forces. The firewall may include fewer seams than a conventional firewall, thereby providing stronger fire resistance. The firewall disclosed herein may have a smooth, non-porous surface that reduces water absorption and in turn reduces product expansion. Because the firewall is designed to be pre-installed in the fill module prior to arriving at the job site, such systems and methods disclosed herein also reduces the amount of time required for field installation of the firewall.
Systems and methods disclosed herein also provide a fill module with a saddle assembly for supporting a header pipe or other distribution pipe of the water distribution system. The saddle assembly allows the header pipes to be installed in the cooling tower after the fill modules are installed. Specifically, the header pipes may be installed by being directly placed on top of the fill modules. Such an advantage may not be present in conventional cooling towers, which typically require the additional installation of a header pipe support beam and a sling upon which to hang the header pipe.
In addition, systems and methods disclosed herein provide an air inlet structure having kitted components such as kitted structural members. “Kitted” means that the components required to build a sub-structure of the air inlet structure are packaged together. Such packaging allows for easier sorting, gathering, and staging of materials for constructing the air inlet structure and thus reduces on-site assembly time and costs. Moreover, such systems and methods may provide an air inlet structure with certain preassembled components such as, for example, certain transverse bents (e.g., diagonal structural members). Such preassembly may further reduce the cost of on-site assembly by, for example, reducing the cost of labor needed to construct and erect the air inlet structure. Such preassembly may also reduce the cost of renting the equipment needed for erecting the air inlet structure.
Systems and methods disclosed herein also provide a cooling tower having components that are transported using a lesser number of trucks than a conventional cooling tower. Specifically, for example, such systems and methods provide fill modules that incorporate the tower structure with the fill unlike conventional fill layers that ship the structure and the fill separately. Thus, such systems and methods request less space for transport. Such systems and methods may also provide a firewall structure integrated into the fill modules that negates separate shipping of the firewall materials and therefore also requires less trucks for transport.
Turning now to
The fill module 100 is configured to be transportable. In particular, the fill module 100 may include certain components that are designed to allow the fill module 100 to be transported under typical transport conditions. For example, the structural system 120 of the fill module 100 may be configured to provide structural support for the fill module 100 when the fill module 100 is being transported. As described above, the structural system 120 may include tension members and compression members that can withstand various tension and compression loads when the fill module 100 is being transported.
In addition, the fill module 100 may include a fastening member such as a U-shaped bolt 130, as depicted in
The firewall 110 of the fill module 100 may also be configured to be transportable. For example, the firewall 110 may be formed of a material with sufficient flexural or bending strength and sufficient tensile strength to withstand any dynamic movements of the fill module 100 during transportation.
The fill module 100 may also include a structural component such as a triangular support structure for supporting the fill packing and other portions of the fill module 100 when the fill module 100 is being transported. For example, the fill module 100 may include a triangular support structure 150.
In other aspects, the fill module 100 may be transported on a surface (e.g., a flatbed) having a width that is equal to or greater than the width of the fill module 100. In such aspects, the entire base of the fill module 100 may be supported by the surface and therefore the fill module 100 may be transported without additional support for any overhang portions.
The triangular support structure 150 may be formed from a subset of the plurality of structural members of the structural system 120. As depicted in
The structural members 220, 230 may be diagonal structural members. As depicted in
When the fill module 100 is being transported and, specifically, when the fill module 100 is being transported on a surface (e.g. the flatbed 200) having a width less than the width of the fill module 100, the triangular support structure 150 may be capable of transferring a load from portions of the fill module 100 that overhang the surface (e.g., overhang portions) to a center portion of the fill module 100. More specifically, the structural members 220, 230 may carry or transfer loads from the respective ends of the structural member 240 to which they are connected to a top of distal end of the structural member 210. The structural member 210 then transfers the loads from its distal end to the center portion of the fill module 100. The center portion of the fill module 100 may be located at a center of the surface. Thus, the structural member 210 may transfer the loads to the center portion of the fill module 100 by delivering a compressive force downward towards the center of the surface. In such an arrangement, the structural member 210 is an example of a “king post.”
Also, when the fill module 100 is being transported, the structural members 220, 230 may be in tension, and the structural members 210, 240 may be in compression. The structural member 220 may be in tension because the first end of the structural member 240 and the top end of the structural member 210 to which it is connected may pull the structural member 220 in different directions. In particular, the portions of the structural member 240 which cantilever over a surface of the flatbed 200 have a propensity to droop or deflect downward. Thus, in order to resist drooping, the diagonal structural members 220, 230 are placed in tension to induce upward components of force and inward horizontal components of force on the first end and the second end of the structural member 240. As such, the structural member 240 is in compression. In addition, the tensile forces in the structural members 220, 230 pull down on the structural member 210 (i.e., the king post), placing it in compression as well.
As depicted in
The triangular support structure 150 of the fill module 100 may be arranged in a symmetrical fashion as shown in
The cooling tower 300 is being assembled at a job site. The assembly may involve constructing the cold water basin 302 and assembling a layer of air inlet structures on the cold water basin 302. The cold water basin 302 may be formed of, for example, reinforced concrete. Assembly of the air inlet structures may include installing a series of transverse bents and diagonal members. Temporary structural (not shown) may be attached to the transverse bents to keep them upright until longitudinal bent framing is installed. To facilitate the installation of the fill modules, certain components of the air inlet structures—such as, for example, structural members disposed near the top of the air inlet structures—may be installed after the fill modules are installed.
As depicted in
When transported, the fill module 352 may be fastened or secured to the carrier using a fastening member such as the U-shaped bolt of the fill module 100. Alignment tubes (not depicted) may also be inserted into the fill module 352 to lock in place a position of the fill packing of the fill modules.
The fill modules may be assembled and delivered to the job site for just-in-time installation. Once at the job site, the fill modules may be hoisted from the carrier and placed on top of the air inlet structures. For example, in
In
The assembly of the cooling tower 300 may continue until the fill modules of the cooling tower 300 are all placed on the air inlet structures, as depicted in
Also depicted in
In
When installed in the cooling tower 300, the structural system of the fill modules and the separate structural systems of the plenum modules may form a portion of the overall support system or “global structural system” of the cooling tower 300. Specifically, as depicted in
Referring now to
As depicted in
The firewall structure 500 may comprise a non-porous surface that is substantially resistant to liquid absorption. As such, the firewall structure 500 may be less susceptible to freezing and thaw damage and biological growth. The water-resistant surface may also reduce product expansion and cracking.
The many features and advantages of the invention are apparent from the detailed specification, and, thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, for example a forced draft air cooled condenser has been illustrated but an induced draft design can be adapted to gain the same benefits and, accordingly, all suitable modifications and equivalents may be resorted to that fall within the scope of the invention.
Jiang, Hongjun, Piskuric, Andjelko
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Executed on | Assignor | Assignee | Conveyance | Frame | Reel | Doc |
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Jul 14 2015 | PISKURIC, ANDJELKO | SPX COOLING TECHNOLOGIES, INC , | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 036317 | /0496 | |
Jul 15 2015 | JIANG, HONGJUN | SPX COOLING TECHNOLOGIES, INC , | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 036317 | /0496 |
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